Valving arrangement for rock drills



Feb. 26, 1963 E. s. OELKE ETAL VALVING ARRANGEMENT FOR ROCK DRILLS FiledFeb. 27, 1961 INVENTORS E'RW/N .S. OELKE EWALD h. KURT Maw THEIRATTORNEY 3,078,827 VALVING ARRANGEMENT FER ROCK DRILLS Erwin S. Oelke,Easton, Pa., and Ewald H. Kurt, Phillipsburg, N.J., assignors toIngersoll-Rand Company, New York, N.Y., a corporation of New JerseyFiled Feb. 27, 1961, Ser. No. 92,023 12 Claims. (Cl. 12110) Thisinvention relates to rock drills in general and more in particular tothat type of rock drill commonly known as down-hole drills.

The type of drill referred to is built to operate at great depths to cutlarge quantities of material. Such material, for commonly known reasons,has to be removed from the hole being drilled, and usually, removal ofthe cuttings is achieved by conducting compressed air through the drilland into the hole being drilled in order to blow out the cuttings fromsuch hole.

In general, the present type rock drills are adapted such that theexhaust of the drill is conducted through an axial passage in thecutting implement or drill bit of the rock drill, the admittance of suchexhaust into the drill bit passage being controlled by means ofcooperation between the piston and two valving arrangements. One valvingarrangement is positioned forwardly of the piston while the othervalving arrangement is positioned rearwardly of the piston. Both valvingarrangements are disclosed in patent application, Serial No. 33,059,filed May 31, 1960, while the valving arrangement rearwardly of thepiston is also disclosed in US. Patent No. 2,951,467. These valvingarrangements include a tube connected to the drill bit, and a tubeconnected to the valve cage, providing telescoping communication duringa part of each stroke of the piston between the associated tube and anaxial passage in the piston. With the latter arrangement a portion ofthe exhaust of the rock drill is valved into the drill bit passage andinto the hole being drilled. As the drill bit is subjected to a highfrequency of heavy impacts, one of the problems is to provide a durableand elfective connection between the tube and the drill bit, aconnection which can withstand the impacts of the piston and consequentsevere vibration and stresses thereof. Another problem is to have thetube connected to either the piston, the drill bit, or the valve cage.

Acordingly, an object of this invention is to provide a rock drillhaving an effective conductance of fluid for cleansing the hole beingdrilled.

Another object of this invention is to provide a rock drill having animproved construction, compared to presently known types of rock drills,to achieve eifective and reliable means for the conductance and valvingof fluid for cleansing the hole being drilled.

Other objects will be in part pointed out and in part obvioushereinafter.

Referring to the drawings,

FIGURE 1 shows a rock drill with a drill bit (partly shown) connectedthereto, partly in longitudinal section,

FIG. 2 is a cross section taken along the line 22 of FIG. 1 looking inthe direction of the arrows,

FIG. 3 is a longitudinal section of a part of the piston shown in FIG. 1showing enlarged the connection between a tube and the forward endportion of the piston.

FIG. 4 is a longitudinal section of a part of the drill bit shown inFIG. 1 showing enlarged the connection between a tube and the drill bit,

FIG. 5 is a longitudinal section of a part of the piston Referring nowto FIG. 1, the rock drill shown comprises a casing 10, partly shown insection, within which is disposed a reciprocatory piston 12 adapted tobe actuated to strike a drill bit 14, partly shown, extending into theforward end portion of casing 10. Drill bit 14 is provided with an axialpassage 16 through which fluid is conducted for cleansing the hole beingdrilled, not shown. Piston 12 is also provided with an axial passage 18through which fluid is conducted to passage 16 of drill bit 14 forcleansing the hole being drilled.

The aforementioned cleansing fluid includes the exhaust of spent motivefluid from within the casing, the control of the flow of such exhaustbeing controlled by a tube 20 connected to drill hit 14, see FIG. 4.Tube 20 is adapted to have a running fit with passage 18 of piston 12.As the tube arrangement shown in FIG. 4 is an improvement of the tubearrangement shown in patent application Serial No. 33,059, filed May 31,1960, reference is made to the aforementioned patent application for thestructure and the operation of the rock drill including the tubecontrolling means.

Referring to the valving arrangements according to this invention, onearrangement is shown in FIGS. l--4. The tube, preferably of an aluminumalloy, is resiliently connectedto either piston 12 or to drill bit 14,such connection being made by expanding a portion of the tube againstresilient means in either the piston or the drill bit to effectresilient transmission of motion between the tube and either the pistonor the drill bit, as to be described hereinafter.

Referring now to FIG. 4, the upper end portion of passage 16 in drillbit 14 is enlarged such that there is provided a passage portion 24having varied cross sectional areas. When the lower end portion of tube20 is inserted in its original form (of uniform diameter such as theupper end portion of tube 20) into such enlarged portion 24 of passage16, there is created a substantial clearance between the outer peripheryof tube 20 and the inner periphery of passage portion 24. In theaforementioned clearance is then disposed a sleeve member of resilientmaterial, preferably polyurethane, and, when the lower end portion ofthe tube is expanded by a predetermined force towards the innerperiphery of passage 24, the resilient material of sleeve 22 iscompressed to a predetermined degree. As tube 20 is expanded into a formas shown in FIG. 4, tube 20 is prevented from being moved out of theassociated portion of passage 16 of drill bit 14. This arrangementcreates a connection between tube 20 and drill bit 14 which is strong,resilient and capable of withstanding the shocks of the impactsdelivered by piston 12 to' drill bit 14. In this manner the transmissionof motion from the drill bit to the tube -is substantially cushioned,providing a tube connection which is stronger and more durable whencompared to the presently known connections.

The connection of tube 20 to piston 12 is illustrated sleeve member 22'and towards the inner periphery -of passage 24, in the same manner asdescribed hereinbefore in connection with the tube connection with drillbit 14. It is to be noted that when the tube is connected to piston 12,as shown in FIG. 1 and FIG. 3, when piston 12 moves away from drill bit14 after having struck drill bit 14, the forward end portion of tube 20'withdraws from passage 16 in drill bit 14. Pressure fluid in the frontend of the casing then escapes through passage 16 of drill bit 14, andtherefrom into the hole being drilled, such operation being similar tothe operation of the tube when connected to the drill bit as describedin detail in the aforementioned patent application.

In presently known rock drills valving of the spent motive fluid fromthe space rearwardly of piston 12 is achieved by cooperation betweenpiston 12 and a tube 26 which is connected to a valve cage 28, see FIG.1, such valving being disclosed in the aforementionedpatentapplications. According to this invention, the tube is connected ,toeither the valve cage 28, see FIG. 1, or to piston 12, see FIG. 5, theconnection between the tube and either the valve cage or the pistonbeing achieved in the same manner as described hereinbefore inconnection with the tube connection with either the drill bit or theforward end portion of the piston.

Referring now to FIG. 6, there is shown still another valvingarrangement, a tube 30 connected to piston 12 such that a portion.32 oftube 30 extends rearwardly of piston 12 while a portion 34- of tube 30extends forwardly of piston 12. The connection of tube 30 to piston 12is achieved in the same manner as described hereinbefore. Valving of theexhaust from the spaces forwardly and rearwar-dly of piston 12, whenapplying the tube arrangement as shown in FIG. 6, is achieved byproviding a passage 36 in valve cage 28 adapted to have a running fitwith portion 32 of tube 30, portion 34 of tube 30 hav- 14, and therefrominto the hole being drilled. When .piston12 is actuatedaway from valvecage 28, portion 32 of tube 30 withdraws frompassage 36 of valve cage28, and spent motive fluid rearwardly of piston 12 then .escapes throughtube 30 of piston ;12,'and therefrom into passage 16 of drill bit 14 andinto thc hole being drilled.

his to be noted that the tube connections according to this invention,as achieved by using a resilient material between the outer periphery ofthe associated tube portion and the inner periphery of the associatedpassage in either the piston, the drill bit, or the valve cage, avoidsdirect contact between the tube and the member to which it is connected,such connection usually causing excessive Wear ofboth members and morein particular of the member made of the softer material. The tubeconnections according to this invention also effects a resilienttransmission of the impacts from either the piston or the drill bit tothe tube, providing a durableand reliable structure.

While there is shown and described specific terms ofthis invention, itis to be understood that various changes and modifications may be madewithout departing from the spirit ofthe invention as set forth in theappended claims.

We claim: 1. In a rock drilling device comprising a casing and areciprocatory first member in said casing, means to conduct fluid toactuate said first member, a second member exteudinginto said casingpositioned to be struck by said first member, said first member providedwith an axial first passage toconduct fluid therethrough, said secondmember provided with an axial second passage to receive fluid conductedthrough said first passage, and conduit meansresiliently'connected tocommunicate with and to extend from the passage of-one ofsaid memberspositioned and adapted to telescopingly communicate with the passage ofthe other of said members duringat least apart of each stroke of theother of said members.

2. In a rock drilling device comprising a casing and a reciprocatoryfirst member in said'casing, means to conduct fluid to actuate'saidfirst member, a second member extending into said casing positioned tobe struck bysaid first member, said first member provided with an axialfirst passage to conduct fluid therethrough, said second member providedwith anaxial second passage to receive fluid conducted through saidfirst passage, and

.a conduit resiliently connected to communicate with and d to extendfrom the passage of said first member positioned and adapted totelescopingly communicate with said second passage in said second memberduring at least a part of each stroke of said first member.

3. In a rock drilling device comprising a casing and a reciprocatoryfirst member in said casing, means to conduct fluid to actuate saidfirst member, a second member extending into said casing positioned tobe struck by said first member to reciprocate whenever such rock drillis operating, said first member provided with an axial first passage toconduct fluid therethrough, said second member provided with an axialsecond passage to receive fluid conducted through said first passage,and a conduit resiliently connected to communicate with and to extendfrom the passage of said second member positioned and adapted totelescopingly communicate with said first passage in said first memberduring at least a part of each stroke of said second member.

4. A movable cutting implement for a rock drilling device provided witha fluid passage therethrough, a conduit having one end portion disposedin said passage and extending exteriorly of said implement to conductfluid, resilient means positioned between the inner periphery of saidpassage and the outer periphery of said end portion of said conduit toresiliently transmit motion from said implement to said conduit wheneversaid implement is moved, said one end portion of said conduit beingexpanded toward the inner periphery of said passage to preventwithdrawal of the conduit from said passage.

5. A movable cutting implement for a rock'drilling device having a fluidpassage therethrough, a portion of .said passage having an area with anirregular surface,

a conduit having one end disposed in said passage and coextensive withat least a part of such area and extending exteriorly of said implementto conduct fluid, and resilient means positioned between the innerperiphery of said passage and the outer periphery of said conduit atsuch area to resiliently transmit motion from said implement to saidconduit whenever said implement is moved, said conduit being expanded atsaid areas to prevent withdrawal of the conduit from said passage.

6. A movable cutting implement for a rock drilling device having a fluidpassage therethrough, a portion of said passage having varied crosssectional areas, a conduit having one end disposed in said passage andcoextensive with at least a part of such areas and extending exteriorlyof said implement to conduct fluid, and resilient means positionedbetween the inner periphery of said passage and the outer periphery ofsaid conduit at at least a part of such areas to resiliently transmitmotion from said implement to said conduit whenever said implement ismoved, said conduit being expanded at the last said areas to preventwithdrawal of the conduit from said passage.

7. In a rock drilling device comprising a casing and means to conductpressure fluid for operating such rock drilling device, a reciprocatoryfirst member in said casing to be actuated by such pressure fluid, asecond member extending into the forward end portion of said casingpositioned to be struck by said first member, a third member positionedrearwardly of said first member adapted to conduct pressure fluid foractuating said first member, each of said members provided with alongitudinal passage for the conductance of fluid, and conduit meansresiliently connected to at least one of said members adapted tocooperate with the passage of one of the other members to valve fluidduring at least a part of each stroke of said first member frominteriorly of said casing to exteriorly thereof.

8. A movable piston for a rock drilling device having a fluid passagetherethrough, a portion of said passage having varied cross sectionalareas, a conduit in said passage having one end portion extending fromone end of said piston and the other end portion of said conduitextending from the other end of said piston to conduct amass? fluid,resilient means positioned between the inner periphery of said passageand the outer periphery of said conduit at at least a part of such areasto resiliently transmit motion from said piston to said conduit wheneversaid piston is moved, said conduit being expanded at said areas toprevent withdrawal of said conduit from said passage.

9. In a rock drilling device comprising a casing and means to conductpressure fluid for operating such rock drilling device, a reciprocatoryfirst member in said casing to be actuated by such pressure fluid, asecond member extending into the forward end portion of said casingpositioned to be struck by said first member, a third member positionedrearwardly of said first member adapted to conduct pressure fluid foractuating said first member, each of said members provided with alongitudinal passage for the conductance of fluid, a conduit connectedto at least one of said members adapted to cooperate with the passage ofone of the other members to valve fluid during at least a part of eachstroke of said first member from the interior of said casing toexteriorly thereof, resilient means positioned between the innerperiphery of the passage in the member to which the said conduit isconnected and the outer periphery of said conduit, said conduit beingexpanded at such area of positioning of said resilient means toresiliently hold said conduit against movement of said conduit relativeto the member to which said conduit is connected.

10. In a rock drilling device comprising a casing and a reciprocatoryfirst member in said casing, a second member positioned rearwardly ofsaid first member adapted to conduct pressure fluid for actuating saidfirst member, said first member provided with an axial first passage toconduct fluid therethrough, said second member provided with an axialsecond passage to conduct fluid therethrough, and conduit meansresiliently connected to communicate with and to extend from the passageof one of said members positioned and adapted to cooperate with thepassage of the other of said members during at least a part of eachstroke of said first member.

11. In a rock drilling device comprising a casing and a reciprocatoryfirst member in said casing, a second member positioned rearwardly ofsaid first member adapted to conduct pressure fluid for actuating saidfirst member, said first member provided with an axial first passage toconduct fluid therethrough, said second member provided with an axialsecond passage to conduct fluid therethrough, and a conduit resilientlyconnected to communicate with and to extend from the passage of saidfirst member positioned and adapted to telescopingly communicate withsaid second passage in said second member during at least part of eachstroke of said first member.

12. In a rock drilling device comprising a casing and a reciprocatoryfirst member in said casing, a second member positioned rearwardly ofsaid first member adapted to conduct pressure fluid for actuating saidfirst member, said first memlber provided with an axial first passag-eto conduct fluid therethrough, said second member provided with an axialsecond passage to conduct fluid therethrough, and a conduit resilientlyconnected to communicate with and to extend from the passage of saidsecond member positioned and adapted to telescopingly communicate withsaid first passage in said first member during at least a part of eachstroke of said first member.

References Cited in the file of this patent UNITED STATES PATENTS1,540,910 Smith June 9, 1925 2,725,214 Lofqvist Nov. 29, 1955 2,859,733Bassinger et al. Nov. 11, 1958 2,947,519 Feucht Aug. 2, 1960 2,951,467Morrison Sept. 6, 1960 2,979,033 Bassinger Apr. 11, 1961

1. IN A ROCK DRILLING DEVICE COMPRISING A CASING AND A RECIPROCATORYFIRST MEMBER IN SAID CASING, MEANS TO CONDUCT FLUID TO ACTUATE SAIDFIRST MEMBER, A SECOND MEMBER EXTENDING INTO SAID CASING POSITIONED TOBE STRUCK BY SAID FIRST MEMBER, SAID FIRST MEMBER PROVIDED WITH AN AXIALFIRST PASSAGE TO CONDUCT FLUID THERETHROUGH, SAID SECOND MEMBER PROVIDEDWITH AN AXIAL SECOND PASSAGE TO RECEIVE FLUID CONDUCTED THROUGH SAIDFIRST PASSAGE, AND CONDUIT MEANS RESILIENTLY CONNECTED TO COMMUNICATEWITH AND TO EXTEND FROM THE PASSAGE OF ONE OF SAID MEMBERS POSITIONEDAND ADAPTED TO TELESCOPINGLY COMMUNICATE WITH THE PASSAGE OF THE OTHEROF SAID MEMBERS DURING AT LEAST A PART OF EACH STROKE OF THE OTHER OFSAID MEMBERS.